Power amplifiers, such as the types of power amplifiers used in wireless communication systems, must be capable of operating at various power levels based on instructions from a controller. A typical prior art power amplifier uses individual pins to control the various functions of the power amplifier. A typical power amplifier may receive signals relating to what band the power amplifier is operating in, and a control signal to control when the power amplifier turns on. A power amplifier may also receive an analog automatic power control signal APC having a power level proportional to the desired output power level.
One problem with prior art power amplifiers is that the their functionality is limited. For example, limitations in the prior art prohibit some features, such as the ability to integrate new functions, or the ability for other devices to read the status of the power amplifier.